Global Patent Index - EP 1035014 A3

EP 1035014 A3 20020102 - Rotor blade for rotorcraft

Title (en)

Rotor blade for rotorcraft

Title (de)

Rotorblatt eines Hubschraubes

Title (fr)

Pale de rotor pour hélicoptère

Publication

EP 1035014 A3 20020102 (EN)

Application

EP 99203091 A 19990921

Priority

JP 6752899 A 19990312

Abstract (en)

[origin: EP1035014A2] A blade root portion (10) of a rotor blade (101) is attached to a rotor head for rotating. A center portion (11) linearly elongates from the blade root portion (10). A blade tip portion (12) outward elongates from the center portion (11) and has a shape which is defined by a leading edge (23), a side edge (25) and a trailing edge (30), and has a predetermined aerofoil. In the leading edge (23) of the blade tip portion (12), a swept-back angle lambda (r) at a distance r from the rotation center of a rotor satisfies relational expression (1) of a rotor blade length R of a rotorcraft, a maximum flight Mach number M INFINITY which is a flight limit speed of the rotorcraft, a blade tip Mach number MTIP which is a tip speed during hovering, and a drag divergence Mach number Mdd which is determined from the aerofoil of the blade tip portion (12). According to this configuration, it is possible to provide a rotor blade for a rotorcraft in which the performance in high-speed flying is improved, the high-speed impulsive noise can be reduced, and a high control performance is attained. <IMAGE> <IMAGE> <IMAGE> <IMAGE>

IPC 1-7

B64C 27/46; B64C 27/467

IPC 8 full level

B64C 27/46 (2006.01); B64C 27/467 (2006.01)

CPC (source: EP US)

B64C 27/46 (2013.01 - EP US); B64C 27/463 (2013.01 - EP US); B64C 27/467 (2013.01 - EP US); Y10S 416/02 (2013.01 - EP US)

Citation (search report)

  • [A] US 4451206 A 19840529 - PHILIPPE JEAN-JACQUES [FR], et al
  • [A] US 4324530 A 19820413 - FRADENBURGH EVAN A, et al
  • [A] DESOPPER A ET AL: "EFFECT OF AN ANHEDRAL SWEPTBACK TIP ON THE PERFORMANCE OF A HELICOPTER ROTOR", VERTICA, PERGAMON PRESS, GB, vol. 12, no. 4, 1988, pages 345 - 355, XP000002903
  • [A] BAEDER J D: "PASSIVE DESIGN FOR REDUCTION OF HIGH-SPEED IMPULSIVE ROTOR NOISE", JOURNAL OF THE AMERICAN HELICOPTER SOCIETY, AMERICAN HELICOPTER SOCIETY. NEW YORK, US, vol. 43, no. 3, 1 July 1998 (1998-07-01), pages 222 - 234, XP000771270, ISSN: 0002-8711

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

DOCDB simple family (publication)

EP 1035014 A2 20000913; EP 1035014 A3 20020102; JP 2000264295 A 20000926; JP 3189251 B2 20010716; US 6190132 B1 20010220

DOCDB simple family (application)

EP 99203091 A 19990921; JP 6752899 A 19990312; US 40482499 A 19990924